Digital archive of theses discussed at the University of Pisa


Thesis etd-01072019-141126

Thesis type
Tesi di dottorato di ricerca
Thesis title
Innovative techniques improving the olive oil nutraceutical quality and the extra virgin olive oil shelf-life
Academic discipline
Course of study
tutor Prof.ssa Zinnai, Angela
controrelatore Dott.ssa Venturi, Francesca
commissario Prof. Andrich, Gianpaolo
commissario Prof. Flamini, Guido
commissario Dott.ssa Bartolini, Susanna
  • storage conditions
  • ripening degree
  • cryogen addition
  • extra virgin olive oil
  • oil quality
  • packaging
  • temperature
  • gaseous atmosphere
  • refining wastewater
  • enriched olive oil
  • sensory analysis
  • volatile compounds
  • bitterness intensity
  • antioxidant capacity
Graduation session start date
Olive oil, used for medical purposes since ancient times, nowadays represents an essential constituent of the Mediterranean diet. In this context the research related to the present PhD thesis was developed. As described below, the aim of the research project was threefold:
- I focus: individuation of the influence of olive ripening degree, irrigation regime and extraction technology adopted on the quality of the EVOO produced. The results showed that olive oil yield and phenolic concentration increased with the ripening degree of the milled fruits and with irrigation regime. The addition of carbonic snow to fruits increased both the yield of oil and the concentration of total phenols dissolved in the olive oils.
- II focus: development of phenol-enriched olive oil with phenolic compounds extracted from wastewater produced by physical refining. The results showed that wastewater collected during the physical refining process could be considered as a good source of bioactive compounds useful for a significant increase of nutraceutical value, as well as of the antioxidant capacity of olive oils.
- III focus: evaluation of the effects of different storage conditions on the shelf-life of EVOO. In particular this aspect has been divided into two experimental projects: a) evaluation of the effectiveness of different conditioner gases on the shelf life of EVOO b) evaluation of the effects of packaging and storage temperature on the shelf life of EVOO. The results showed that argon treatment appears as the best solution alternative to nitrogen to preserve the quality of the EVOO over time and the storage in greenish glass at 6 °C, could represent a promising storage condition to slow-down the oil degradation during market storage.